Production of motor gasoline by a twostage reforming process



United States Pate'ntO PRODUCTION OF Moron GAS QLINE BY A Two- STAGE REFORMING PROCESS Warren Nevin Norton Knight, Sunbury-on Thames, Englangl, assignor to The British Petroleum Company Limited, London, England, a British joint-stock corporation No Drawing. Filed Rec. 7, 1956, Ser. No. 626,821 Claims priority, application Great Britain Dec. 19, 1955 5 Claims. (Cl. 208-65) This invention relates to the production of high octane motor gasoline of good volatility.

Catalytic cracking and hydroforming are among the processes which contribute to the production of high octane gasolines. In the catalytic cracking process, a petroleum feedstock boiling above the gasoline boiling range is cracked in the presence of a catalyst to produce hydrocarbons boiling in the gasoline boiling range, while in the hydroforming process, petroleum naphthas that have a low octane number are contacted at elevated temperature and pressure in the presence of hydrogen with a catalyst capable of converting naphthenes into aromatics to give a product of greatly increased octane number. A hydroforming process that has been widely adopted uses a platinum-containing catalyst, and such a process will hereinafter be referred to as platinumcatalyst-hydroforming. The aparatus for carrying out such a process will be referred to hereinafter as a platinum-catalyst-hydroformer and the product of such process as platinum-catalyst-hydroformate. In order to obtain a gasoline having an octane number greater than 100 Research (clear) and of adequate volatility, it has been proposed to thermally reform the platinum-catalyst-hydroformate to increase its octane number, and to blend the thermally reformed platinum-catalyst-hydroformate with a light catalytically cracked gasoline to give a product of sufiiciently high volatility.

The feedstock to the platinum-catalyst-hydroforming process is commonly a heavy naphtha having a boiling range of, for example, 90-190 C. ASTM, and this results in a large excess of a fraction having a boiling range of C 90 C. ASTM, and a low octane number of about 65 Research. Only limited quantities of this low octane number material can be disposed of by blending into motor gasoline, and severe thermal cracking will not increase its octane number sufilciently to make it suitable as a blending component for high octane gasolines.

The present invention has among its objects to enable motor gasolines having a high octane number and adequate volatility to be produced without the use of catalytically cracked gasoline as a blending component. It is also an object of the invention to make use of a light straight-run gasoline, of the kind obtained in the preparation of the platinum-catalyst-hydroformer feedstock, in the production of high octane gasolines.

According to the present invention, a high octane gasoline of adequate volatility is produced by thermally reforming a mixture of a p1atinum-catalyst-hydroformate and a light straight-run gasoline.

The light straight-run gasoline is advantageously a fraction of crude petroleum boiling below the boiling range of the feedstock to the platinum-catalyst-hydroforming process.

The feedstock to the platinum-catalyst-hydroforming operation should boil within the range 80-200 C., and should be platinum-catalyst-hydroformed to an octane number of at least 90 (Research) in order by the process ice of the invention to produce motor gasolines' having an octane number of at least 100 Research (clear) and a volatility of at least 45% vol. recovered at 100 C. It is to be understood, however, that the invention is not to be limited to the production of such gasolines.

The proportions of platinum-catalyst-hydroformatc and light gasoline in the mixture subjected to thermal reforming will depend on the volatility and octane num ber of the two components, and the volatility and octane number required in the final gasoline. The thermal reforming should preferably be carried out under the following conditions:

Temperature l000 to 1200 F. Pressure 200 to 1200 p.s.i.g. Conversion 5% to 25% wt. C and lighter.

The invention will now be described with reference to the following example.

Example A straight-run Kuwait naphtha (90190 C. ASTM boiling range) was platinum-catalyst-hydroformed to give a yield of wt. gasoline of 95 research octane number and a volatility of 44% vol. evaporated at 100 C. This material was mixed with a Kuwait straight-run light gasoline (C 90 C. ASTM boiling range), which had a research octane number of 65.5, in the proportion 70/30 by volume platinum-catalyst-hydroformate gasoline. This mixture was thermally reformed at 1060 F. and 750 p.s.i.g. to a conversion of 18% wt. C and lighter and the resultant gasoline (70% wt. yield on reformer feed) had a research octane number of 100 clear and a volatility of 47% vol. evaporated at 100 C.

I claim:

1. A process for the production of a gasoline having an octane number of at least 100 Research (clear) and a volatility of at least 45 volume recovered at 100 C., which comprises contacting a straight-run petroleum fraction boiling within the range 200 C. in the presence of a platinum catalyst and at elevated temperature and pressure, recovering a platinum catalyst hydroformate having an octane number of at least Research (clear), mixing said recovered hydroformate with a light straight-run gasoline fraction boiling below the boiling range of the untreated fraction, subjecting said mixture to thermal reforming at a temperature of l000 to 1200 F. and a pressure of 200 to 1200 p.s.i. ga., and recovering a gasoline having an octane number of at least Research (clear) and a volatility of at least 45% volume recovered at 100 C.

2. A process in accordance with claim 1 wherein the petroleum fraction is a petroleum naphtha boiling within the range 90 to C., the straight-run gasoline is a gasoline boiling below 90 C., and the convers on in said thermal reforming is 5% to 25% of C and lighter.

3. A process in accordance with claim 1 wherein the hydroformate is blended With said gasoline in the ratio of 70 parts by volume of said hydroformate to 30 parts by volume of said gasoline.

4. A process for the production of a gasoline having an octane number of at least 100 Research (clear) and a volatility of at least 45% volume recovered at 100 C. from a straight-run gasoline which comprises separating the straight-run gasoline into a heavy na htha fraction which boils within the range 80 to 200 C., and a light gasoline fraction boiling below the boiling range of said heavy naphtha fraction, subjecting said heavy naphtha fraction to catalytic platinum hydroforming at elevated temperature and pressure, recovering a platinum catalyst hydroformate having an octane number of at least 90 Research (clear), mixing said hydroformate with said light gasoline fraction, and subjecting said mixture Pat ted Dec. 6, 196a to thermal reforming at a temperature of 1000 to 1200 F. at a pressure of 200 to 1200 p.s.i. ga., and recovering a gasoline having an octane number of at least 100 Research (clear) and a volatility of at least 45% recovered at 100 C.

5. A process in accordance with claim 4 wherein the heavy naphtha fraction boils within the range 90 to 100 C., and said light gasoline fraction boils within the range C 9O C., and the conversion of said thermal reforming is 5% to 25% of C and lighter.

References Cited in the file of this patent UNITED STATES PATENTS Diwoky July 15, Gilbert July 16, Haensel Aug. 16, Welty Dec. 6, Haensel Jan. 4, Watkins Oct. 9, 

1. A PROCESS FOR THE PRODUCTION OF A GASOLINE HAVING AN OCTANE NUMBER OF AT LEAST 100 RESEARCH (CLEAR) AND A VOLATILITY OF AT LEAST 45% VOLUME RECOVERED AT 100*C. WHICH COMPRISES CONTACTING A STRAIGHT-RUN PETROLEUM FRACTION BOILING WITHIN THE RANGE 80*-200*C. IN THE PRESENCE OF A PLATINUM CATALYST AND AT ELEVATED TEMPERATURE AND PRESSURE, RECOVERING A PLATINUM CATALYST HYDROFORMATE HAVING AN OCTANE NUMBER OF AT LEAST 90 RESEARCH (CLEAR), MIXING SAID RECOVERED HYDROFORMATE WITH A LIGHT STRAIGHT-RUN GASOLINE FRACTION BOILING BELOW THE BOILING RANGE OF THE UNTREATED FRACTION, SUBJECTING SAID MIXTURE TO THERMAL REFORMING AT A TERMPERATURE OF 1000* TO 1200* F. AND A PRESSURE OF 200 TO 1200 P.S.I. GA., AND THE RECOVERING A GASOLINE HAVING AN OCTANE NUMBER OF AT LEAST 100 RESEARCH (CLEAR) AND A VOLATILITY OF AT LEAST 45% VOLUME RECOVERED AT 100*C. 